On Day 8, all of our interns continued working on the physical prototyping of their AR box, programming their Arduino to control all the interactive components, and perfecting the app they were developing to give visitors access to the final project. One of our interns, Emanuel Gordis, focused on taking apart and modifying a fog machine to use in his team's project which focused on carbon emissions in an urban landscape.

Emanuel's goal was to to be able to create a bluetooth enabled fog machine controlled by an arduino. At first, there was no obvious way to do that, but he was determined to figure it out. With the help of one of our volunteers, Dominic Dighera, he was able to analyze the button used to turn the fog machine on. He needed to understand what part of the circuit the button was closing and replace it with a relay that allowed him to turn the machine on and off. He used a relay because it allowed him to switch high voltage alternating current using the low voltage digital pin output of the arduino.

First, Emanuel needed to design a circuit to implement the relay. Since the relay didn't fit onto a bread board, his circuit needed to be soldered onto a protoboard instead and tested using a multi-meter. He needed to conduct continuity tests which confirmed his circuit was soldered together properly. Then he needed to perform a functionality test using a 9V battery to close the relay. Once this all worked, he had successfully built a circuit that turned on his fog machine!

His next steps are to implement a fan to blow the fog out of the box so it doesn't completely block the Raspberry Pi camera's view as it streams to the Google Cardboard headset. His big goals are to connect it in a very similar way to an external, higher voltage power supply and figure out a way to use his arduino to control it via bluetooth. We can't wait to see how he uses this fog machine in his final project!